$\vec v = (-2,-4)$ $2\vec v= ($
Answer: In general, the scalar multiple of $k$ times $\vec u$ is this: $k\vec u = k(u_x, u_y) = (ku_x, ku_y)$. So, here's how we find $2 \vec{v}$ : $\begin{aligned} {2}\vec v = {2} \cdot (-2,-4) &= \left({2} \cdot (-2), {2} \cdot (-4)\right) \\\\ &= (-4,-8) \end{aligned}$ The answer is $ (-4,-8) $.